13 days ago my son was diagnosed with croup and asthma. He was started on nebulizer treatments 4 times a day, which we have been doing for 13 days now. He has also been on prelone for 5 days, and amoxil for 6 days. He had a chest x-ray because the pediatrician said croup is only supposed to last for 10 days. The x-ray showed something behind the left ventricle of the heart, but they couldn't be sure if it was pneumonia and want to do another x-ray. He is no better on day 13 than he was on day one. He also has yellow/green junk from his nose.

With croup symptoms that show no sign of improvement after 5 days of prelone, it's time to think of other possible causes -- especially with an unidentified something on the chest x-ray.

An inhaled foreign body can cause croup, and would not respond to treatment. Pneumonia could be the cause. Mycoplasma is also possible. Mycoplasma wouldn't respond to amoxicillin; it would need a different antibiotic.

Croup is typically caused by parainfluenza viruses and is over quickly, but it can also be caused by longer-lasting viruses such as RSV (respiratory syncytial virus), especially in kids with asthma.

In any event, unless the x-ray was read by a pediatric radiologist, I would be in favor of getting a second opinion for your 8-month-old son. The closest children's hospital would be a good place, and could also direct you to the best place close to you. Most children’s hospitals have a parents’ advice line to get you steered in the right direction.